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MrJohz | on: Lies I was told about collaborative editing, Part 2: Why we don't use Yjs
Are there any major libraries for OT? I've been looking into this recently for a project at work, and OT would be completely sufficient for our use case, and does look simpler overall, but from what I could tell, we'd need to write a lot of stuff ourselves. The only vaguely active-looking project in JS at least seems to be DocNode (https://www.docukit.dev/docnode), and that looks very cool but also very early days.
antics | parent | next
Author here. I think it depends what you're doing! OT is a true distributed systems algorithm and to my knowledge there are no projects that implement true, distributed OT with strong support for modern rich text editor SDKs like ProseMirror. ShareJS, for example, is abandoned, and predates most modern editors.

If you are using a centralized server and ProseMirror, there are several OT and pseudo-OT implementations. Most popularly, there is prosemirror-collab[4], which is basically "OT without the stuff you don't need with an authoritative source for documents." Practically speaking that means "OT without T", but because it does not transform the ops to be order-independent, it has an extra step on conflict where the user has to rebase changes and re-submit. This is can cause minor edit starvation of less-connected clients. prosemirror-collab-commit[5] fixes this by performing the rebasing on the server... so it's still "OT without the T", but also with an authoritative conflict resolution pseudo-T at the end. I personally recommend prosemirror-collab-commit, it's what we use, and it's extremely fast and predictable.

If you just want something pedogocically helpful, the blessed upstream collaborative editing solution for CodeMirror is OT. See author's blog post[1], the @codemirror/collab package[2], and the live demo[3]. In general this implementation is quite good and worth reading if you are interested in this kind of thing. ShareJS and OTTypes are both very readable and very good, although we found them very challenging to adopt in a real-world ProseMirror-based editor.

[1]: https://marijnhaverbeke.nl/blog/collaborative-editing-cm.htm...

[2]: https://codemirror.net/docs/ref/#collab

[3]: https://codemirror.net/examples/collab/

[4]: https://github.com/ProseMirror/prosemirror-collab

[5]: https://github.com/stepwisehq/prosemirror-collab-commit

MrJohz | root | parent | next
In our case, we're not using a text editor, but instead building a spreadsheet, so a lot of these collab-built-into-an-editor are, like you say, pedagogically useful but less helpful as direct building blocks that we can just pull in and use. But the advice is very useful, thank you!
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GermanJablo | parent | next
Author of DocNode here. Yes, it’s still early days. But it’s a very robust library that I don’t expect will go through many breaking changes. It has been developed privately for over 2 years and has 100% test coverage. Additionally, each test uses a wrapper to validate things like operation reversibility, consistency across different replicas, etc.

DocSync, which is the sync engine mainly designed with DocNode in mind, I would say is a bit less mature.

I’d love it if you could take a look and see if there’s anything that doesn’t convince you. I’ll be happy to answer any questions.

MrJohz | root | parent
I've looked through the site, and right now it's probably the thing I'd try out first, but my main concerns are the missing documentation, particular the more cookbook-y kinds of documentation — how you might achieve such-and-such effect, etc. For example, the sync example is very terse, although I can understand why you'd like to encourage people to use the more robust, paid-for solution! Also just general advice on how to use DocNode effectively from your experience would be useful, things like schema design or notes about how each operation works and when to prefer one kind of operation or structure over another.

All that said, I feel like the documentation has improved since the last time I looked, and I suspect a lot of the finer details come with community and experience.

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